Get the list of available apps from /xml/app_info.json:


    "App": [
            "Name": "Amazon S3",
            "Package": "AmazonS3",
            "Version": "1.21",
            "Image": "",
            "Icon": "",
            "ReleaseNotes": "",
            "MinFWVer": "5.27.100",
            "MaxFWVer": "",
            "desc": {
                "en-US": "Amazon S3 (Simple Storage Service) is an online file storage web service offered by Amazon Web Services. It provides storage through web services interfaces to backup data on your device to the cloud."
        { /* ... */ },

The app image can be found in the App[].Image attribute (example:

According to the file command the file just contains… data:

$ file MyCloudEX2Ultra_AmazonS3_1.21.bin 
MyCloudEX2Ultra_AmazonS3_1.21.bin: data

The binwalk command shows that the file contains gzip compressed data which is more interesting:

$ binwalk MyCloudEX2Ultra_AmazonS3_1.21.bin 

204           0xCC            gzip compressed data, from Unix, last modified: 2023-03-29 08:00:50

Use binwalk to extract the gzip data:

$ binwalk --include gz --extract MyCloudEX2Ultra_AmazonS3_1.21.bin
$ ls
MyCloudEX2Ultra_AmazonS3_1.21.bin  _MyCloudEX2Ultra_AmazonS3_1.21.bin.extracted

We now have a folder called _MyCloudEX2Ultra_AmazonS3_1.21.bin.extracted containing the extracted data

$ cd _MyCloudEX2Ultra_AmazonS3_1.21.bin.extracted
$ ls
$ file CC
CC: POSIX tar archive (GNU)
$ tar xf CC